#修改元素
my_set = {1, 2, 3}
my_set.remove(2)
my_set.add(4)
print(my_set)
# 查询元素
set1 = {1, 2, 3, 4, 5}
set2 = {3, 4}
is_supbest = set1.issubset(set1)
is_supberst = set1.difference(set2)
difference = set1.difference(set2)
print(is_supbest)
print(is_supberst)
